JPH0832579B2 - Heat treatment method of intumescent material for forming lightweight aggregate and its treatment apparatus - Google Patents

Abstract

Expansion of granular or particulate material is effected by supplying such material, for instance slate chips, at a charging zone CZ of a kiln 10, to the upper surface of a rotating annular hearth 12 so as to lie thereon in a uniform layer up to about three chips in thickness. The hearth 12 is rotating in the direction of the arrow 96, and the chips face thereon just after a preheating zone PHZ. The chips are carried successively through a treatment zone TZ wherein they are subjected to heat from regenerative burner arrangements 68, 70 and 64, 66 beneath hood 44, to a discharge zone DZ whereat they are loosened by a reciprocating rake 80, 82 and are blown off the hearth 12 and into a receiver 88 by air jets from radially directed nozzles 78 supplied by way of a manifold 76.The kiln, and its manner of use, enables expansible material, such as slate chips, to be substantially fully expanded and thereby achieve a product, suitable for use as a lightweight aggregate, of minimum possible density.

Description

Description: TECHNICAL FIELD The present invention relates to a heat treatment method for an expandable particulate material and a treatment apparatus therefor for forming a lightweight aggregate having excellent heat insulation used in the construction industry. .

(Prior art and its problems) In the construction industry, it has recently become very important to produce lightweight aggregate having excellent heat insulating properties. In the UK in recent years, the legal conditions for allowable heat transfer coefficient of building walls have become more and more strict, and as a result, the materials traditionally used until now are no longer used for buildings and structures. Is no longer appropriate.

For example, one example of conventional aggregate is a well-known lightweight concrete block having an aggregate made of cement-hardened hard brick for the furnace. The insulating properties of such blocks do not meet legal requirements unless extremely broad pressure objects are used, and as far as light aggregate concrete is concerned, there are only a few commercially available products used in the UK. Only blocks can meet the above conditions.

Also, the use of lightweight aggregate is not limited to the production of building blocks, but is widely used in the building industry. For example, the formation of concrete on the part where it is originally used, precast concrete panels, lightweight concrete roof planks, filling of hollow cavities, lightweight concrete structures, and many other locations where low thermal conductivity and lightness are required. Is used for.

Generally speaking, the insulation properties of lightweight concrete are inversely proportional to the specific gravity, in other words the thermal conductivity increases in proportion to the specific gravity, and therefore the lightweight aggregate concrete or part of such building blocks. It is desirable to make the specific gravity as small as possible for the aggregate.

Further, since the heat transfer coefficient increases within a certain area due to the presence of water, it is desirable for the building block and the lightweight concrete that the aggregate in them has the property of not absorbing water.

It has been attempted to form a lightweight aggregate by heat treating various natural materials such as slate, viscosity and shale. When it comes to suitable slate pieces, there are hundreds of thousands of tons of useful slate material.

When slate or clay in a raw material state is originally incorporated as an aggregate in a concrete block, a lightweight concrete cannot be formed as a result. However, it can be formed into a suitable lightweight aggregate as part of the lightweight aggregate concrete by expansion or "bloated" by suitable heat treatment. As a result, when used as such, lightweight concrete has excellent thermal insulation properties and sufficient compressive strength for various purposes.

As already mentioned, attempts to expand slate to form lightweight aggregates have been made in the past, but due to practical difficulties, high fuel consumption and some environmental restrictions, commercial and economic There are few production methods that can be implemented.

In addition, most of the production methods proposed so far have not yet produced a sufficiently expanded product, but only achieved partial expansion.

As the manufacturing method and apparatus used so far, for example, an inclined rotary furnace is used, slate chips are supplied from the upper end of the rotary furnace, and reach the lower end of the other end, from which they are It is supposed to be discharged. However, in the process of passing through the rotary furnace, it is presumed that the chips roll each other and expand so as to receive the heat in the rotary furnace.

However, the actual rotary furnace temperature is limited to below the optimum conditions for expansion. The reason for this is that if the temperature is not limited as described above, at least partially melted slate adheres to each other and adheres to the inner surface of the furnace during the expansion process. This is known as linking, which also has the adverse effect of impeding the passage of material through the furnace during the production process and reducing the efficiency of material passage.

As a result, conventionally only a partially expanded slate can be produced, whereby the specific gravity of the product is
It has a very large specific gravity when compared to the specific gravity of the slate if it is assumed to be fully expanded. Furthermore, the difficulty of effective heat recovery leads to high fuel consumption.

(Object of the Invention) An object of the present invention is to expand a material such as slate or clay having expandability in order to form a lightweight aggregate.
A method for the heat treatment of granular or particulate material, which expands the material to the maximum possible degree of expansion of the material without suffering the above disadvantages, thereby reducing the specific gravity of the material to the maximum possible small specific gravity. And to provide the device.

(Means for Solving the Problem) The present invention is a heat treatment method for fine particles having expandability such as slate chips or clay pellets,
And it produces a lightweight granular product. Granular products are also those used, for example, in the production of lightweight concrete blocks.

The heat treatment method according to the present invention comprises a step of supplying a material to a moving hearth in a supply zone and a step of passing the hearth through a processing zone so that the material can be distributed from above onto the hearth. And having a step of exposing the material to a high temperature between 1100 ° C. and 1300 ° C. so as to at least partially melt so as to expand the material, and a step of discharging the expanded product from the hearth in the discharge zone, , The hearth preheats the empty hearth by passing through the preheating zone before reaching the feed zone, and the supply of particles to the hearth in the feed zone is above the hearth. 1 to 3 particles
The layer of particles is formed to have a thickness of about a grain.

Preferably, the expanded product is cooled during the discharge stroke. The cooling is effectively achieved, for example, by blowing a fluid such as air or steam in the discharge zone.

While passing through each zone, there is no movement of an important relationship between each particle and the hearth or between the particle and the hearth, and the phenomenon that particles adhere to each other or particles adhere to the hearth It can be kept to a minimum.

In practicing the present invention, it is advantageous to have an endless structure for the hearth so that, at any one time, different hearth sections are located at positions corresponding to the various zones enumerated above. To achieve this, the hearth consists of a number of tiles that are next to each other or connected to each other, and these tiles have excellent heat resistance, such as silicone carbide, and are rigid and chemically non-toxic. Made of active material.

In some devices, the tiles are square shaped and flexibly connected to each other along the perimeter of a suitable roller or drum, such as in an endless belt assay. The horizontal transport stroke above the tile assay includes a feed zone, a treatment zone, a discharge zone and a preheat zone, when provided.

In the preferred apparatus, the hearth is formed in the shape of a disk plate or an annular plate, and preferably has a number of tiles arranged adjacent to each other or connected to each other, and a rigid horizontal plane can be rotated about a rigid vertical axis. ing. The hearth is largely covered by one or more housings, which form the feed zone, the treatment zone, the discharge zone and possibly the preheating zone.

The treatment zone is surrounded by a suitable housing part and is constructed, for example, in a furnace type with a regenerative burner. Regenerative burners can minimize the fuel supply needed to heat the material during processing. If possible, the preheating zone is also configured as a furnace with a regenerative burner similar to the above.

When utilizing expanded slate chips to produce, for example, high quality, low specific gravity concrete, concrete blocks and light weight particulate material suitable for use in the production of such products and structures, In the zone
It is preferable to expose the material to temperatures between 1100 ° C and 1300 ° C, especially around 1250 ° C, and 900 ° C to 1100 ° C in the discharge zone.
During this, it is preferable to lower the temperature to 1050 ° C.

An annular furnace type device suitably rotates at a speed of one revolution in 1.5 to 4.5 minutes. In the present invention, it is preferable to partition each zone by the following angles in the circumferential direction and the ratio to the total area of the hearth.

Percentage of entire zone Center angle range Preheating zone 25-40% 90-144 degrees Supply zone 3-8% 10.8-28.8 degrees Treatment zone 62-37% 223.2-133.2 degrees Discharge zone 10-15% 36-54 degrees (Implementation Example) The examples shown in FIGS. 1 to 6 show, for example, one embodiment of the present invention suitable for expanding particles in the state of slate chips. The slate chips are, for example, those of North Wales. It is made by crushing slate fragments from the Braunau Festinio region.

In each of the drawings of this embodiment shown in FIGS. 1 to 6, an annular furnace device 10 is used.

The furnace apparatus 10 comprises an annular hearth 12, which comprises a number of refractory tiles made of, for example, silicone carbide.
It is formed by 14. The refractory tiles 14 are supported in an annular arrangement on an annular bed 16 of insulating material, the annular bed 16 being arranged on an annular top plate 18 of an annular carrier. The annular carrier has a radial cross-section (vertical cross-section)
Is formed in a box shape, and is composed of the top plate 18, the bottom plate 22, and a reinforcing spacer 20 connecting the both plates 18, 22. An annular carrier (18, 20, 22) is supported on the outer portion of the radial arms 24 of the spider 26. The spider 26 is fixed on a rotating ring 28 supported on a pedestal 30 so as to be rotatable about a vertical axis, and rotates together with the rotating ring 28 about a vertical axis concentric with the central axis of the annular hearth 12. It is free. A drive gear 32 is formed on the outer periphery of the rotary ring 28. The drive gear 32 is meshed with a pinion 34 of a gear box 36, and the gear box 36 is linked to an electric motor 38. That is, the rotation of the electric motor 38 causes the hearth 12 to rotate about the central vertical axis via the gear box 36, the pinion 34, the drive gear 32 and the rotating ring 28, and the rotation speed thereof makes one rotation every 1.5 to 40 minutes. It's speed.

A heat shield furnace hood 44 having an inverted U-shaped cross section is arranged on the hearth floor 12 so as to cover substantially the whole of the hearth floor 12, and the furnace hood 44 is an upper structure composed of a plurality of cross members 40 and the like. Suspended from above by the body, the superstructure has multiple legs 42
Supported by The upper structure is omitted in FIG. As shown in FIG. 2, the hood 44 is provided with a gap to secure the supply zone CZ and the discharge zone DZ. The hood 44 comprises a number of ceramic or refractory brick sections lined with, for example, insulation, the discharge zone DZ and the supply zone.
The area that covers the hearth 12 between the CZs is configured as a preheating zone PHZ and a processing zone TZ.

The prediction heating zone PHZ has a circumferential angle of 135 degrees and occupies 37.5% of the total area of the hearth 12. The processing zone TZ has a circumferential angle extending over 160 degrees and occupies 44.5% of the total area of the hearth 12. Supply zone
The CZ has a circumferential angle of 20 degrees, which is 5.
Occupy 5%, the discharge zone DZ circumferential angle is 45 degrees,
It accounts for 12.5% of the total area of the hearth 12.

As shown in FIG. 2, in the range of the supply zone CZ, an opening 46 is formed at the upper end of the hood 44, so that an inflatable material such as a slate tip is supplied therethrough as shown in FIG. Makes it possible. In order to achieve the material supply as described above, the hood 44 should be placed horizontally from the outside.
A chute plate 50 protruding inside is arranged, and the chute plate 50 is
Are rigid and formed in a flat plate shape, and are gathered at the inclined bank end 52. The bank edge portion 52 linearly crosses the entire radial width of the hearth 12 and extends along the radial direction of the hearth 12. The chute plate 50 is supported by a flexible support 54, and the support 54 is connected to a vibration motor 56 so that the chute plate 50 is vibrated in its longitudinal direction by the operation of the motor 56. A hopper 58 supported by a carrier plate 60 is arranged for feeding the slate chips 48 to the chute plate 50. The carrier plate 60 is interlocked with another vibrating motor 62, which vibrates lengthwise by the motor 62 and feeds the chips 48 onto the chute plate 50.

The above arrangement structure provides a uniform slate chip layer with an annular hearth 12
It is extremely effective to supply to. A uniform layer is three grains thick of chips, preferably two grains thick.
The supply rate of chips per hour is, of course, controlled by various suitable methods. For example, it is performed by controlling the frequency and the vibration width of the carrier plate 60 and the chute plate 50.

In the treatment zone TZ and the preheating zone PHZ, a series of regenerative burner devices are arranged as heating means. In the illustrated embodiment, one half of the processing zone TZ in the circumferential direction is provided with complementary first burner sets 64, 66 facing each other with the processing zone TZ sandwiched between them, and the other half of the remaining half is provided with the remaining Complementary second burner sets 68, 70 are arranged facing each other across the treatment zone portion. Further, in the preheating zone PHZ, there are arranged complementary third burner sets 72, 74 facing each other with the preheating zone PHZ interposed therebetween. As is well known, a regenerative burner device is one of a set of burners in which one burner is supplied with combustible fuel and air and heats a corresponding part of the furnace to pass through the part. The latter combustor supplies heat by passing to opposing complementary burners and through a heat storage section which retains and stores the remaining heat contained in such combustor. As soon as the accumulated heat reaches a predetermined level, the roles of the two burners are replaced and the accumulated heat is used to preheat the combustion air supplied to the working burner.

The illustrated burner device has a processing zone TZ of 1250 degrees to 1300 degrees.
Controlled to maintain a temperature of 10 degrees and also a preheating zone
Controlled to maintain the PHT at a temperature around 1250 degrees.

As shown in FIGS. 4, 5, and 6, in the discharge zone DZ, a manifold pipe 76 that crosses over the hearth 12 in the radial direction is arranged, and the manifold pipe 76 has a radius of the hearth 12. Multiple tilted nozzles 78 facing outward and downward
Is provided. The manifold pipe 76 is connected to a compressed air source (not shown) and supplies compressed air to each nozzle 78, thereby continuously supplying an air flow from the nozzle 78 to the material on the hearth 12. .

In the discharge zone DZ, a rake bar 80 extending radially across the hearth 12 is arranged in parallel with the manifold pipe 76. It is supported. The bar 80 is formed in a hollow cylindrical shape, and is cooled by passing air through it. The rake bar 80 is also configured to be reciprocally movable in its longitudinal direction. This rake bar
A large number of heat-resistant metallic tins 82 are formed on the 80, and the tins 82 are inclined downward from the bar 80, and the lower end of the tin 82 is placed on the upper surface of the hearth 12. The tines 82 are arranged in a row near the nozzle 78. Bar to bar 80
A weighting arm 86 extending in the radial direction of 80 is fastened, and a weight 84 is provided on the arm 86 at a position apart from the center of the rake bar. The weight of the weight 84 biases the bar 80, which causes the tin 82 to be in the hearth.
It is pressed against the upper surface of 12 with a constant pressure. The weight 84 is movable and adjustable along the length of the arm 86, and the pressing pressure of the tin 82 can be adjusted by adjusting the position of the weight 84. With such a structure,
The tin 82 can also overcome unevenness at the joint between the adjacent tiles 14 forming the hearth 12. Discharge zone
Within the range of DZ, a product receiving box 88 is arranged on the side of the hearth 12 and is discharged radially outward from the hearth 12 by the air injection of the nozzle 78 in the box 88. Material is input.

The rake bar 80 is a rod as shown in FIGS.
94, a variable electric motor 90 via a crank 92, and is reciprocally movable in the longitudinal direction thereof, whereby each tin 82 moves from the hearth 12 rotating therebelow to the hearth. It reciprocates in the radial direction of 12, first in the outward direction and then inward.

The operation of the apparatus described above and the preferred method of manufacture according to the invention are described in detail below. When the furnace is started, first an operating temperature of 1300 degrees is created so that at least the slate chips in the processing zone TZ are partially melted. The air supplied to the nozzle 78 through the manifold pipe 76 is
It is an air that lowers the material temperature to 1050 degrees, which is sufficiently lower than the melting temperature of slate.

As shown in FIGS. 2 and 4, the hearth 12 is driven to rotate in the direction of arrow 96, and the vibration motors 56 and 62 are set to the operating state. As a result, the slate chips 48 are provided on the hearth 12 in a uniform layer not exceeding a thickness of 3 grains of chips 48, preferably a uniform layer having a thickness of 1 or 2 grains of chips.

This layer of chips 48 is first heat treated by passing through a treatment zone TZ. The slate chip expands during this heat treatment process. Actually the tip is just 2
Although it has a thickness of about 4 mm, it is expanded to a thickness of about 4 to 5 times the initial thickness, that is, a thickness of 8 to 20 mm by being heated in the treatment zone TZ for an appropriate time, and at the same time, the initial thickness is increased. specific gravity
2.6-2.8 decreases to the specific gravity of 0.6.

In fact, the maximum stage of chip expansion is achieved by the initial heating of the outer peripheral surface of each chip to effect the initial melting quickly. Each chip is sealed on the outer peripheral side, and as a result of heat permeation, the gas sealed so as not to leak to the outside expands, and maximum expansion is achieved. It should be noted that with slow heating, gas escapes and expansion loss occurs, resulting in a product with a large specific gravity. This is a drawback of the conventional method of heating the material while rolling it, for example in an inclined converter.

After passing through the treatment zone TZ at a speed sufficient to ensure sufficient expansion, the particles or chips 48 reach the discharge zone DZ, where they encounter the reciprocating tin 82,
Make sure that no material adheres to the hearth 12 and that it is separated from the hearth 12 and that the air from the nozzle 78 causes some melting back
Cooled down to around 1050 degrees, and the expanded particles reliably return to the solid state. The air from the nozzle 78 also carries the expanded particles by the air stream from the top of the hearth 12 radially outward and into the receiving box 88.

The emptied hearth 12 then passes through a preheating zone PHZ, where the temperature of the hearth 12 is heated to a suitable operating temperature of around 1250 degrees Celsius, then returns to the feed zone CZ and the next new chip is as before. Supplied.

As described above, the device can be used in a continuous and continuous process.

The method according to the invention is particularly, but not exclusively, effective when using slate fragments produced from a slate mine in the Branaufestini region of North Wales. The above mining sites produce a tremendous amount of slate debris that has never been used so far.

According to actual tests, when fully expanded chips are used for concrete aggregate, it is a lightweight aggregate that is extremely suitable for use in the production of structural blocks and other structural materials with excellent pressure resistance and / or heat insulation. Can be provided.

Although the expanded material is itself highly porous, such pores are closed pores and therefore do not absorb water when exposed to water for many months. Each swollen particle will have a number of closed pores encapsulated in a hard impermeable skin, thereby ensuring non-absorption of water. Due to such water resistance characteristics, it is possible to use the expanded slate as an aggregate of concrete which does not suffer the following disadvantages due to water absorption. That is, the above disadvantage is that when a very small amount of water penetrates into the lightweight aggregate for concrete, the water content thereof causes a sharp decrease in heat insulation. Blocks made from expanded slate have reached legal standards for thermal insulation properties, they are particularly light in weight and have excellent water resistance, so they are not affected by movement or dimensional changes. .

Of course, the method of the present invention is not limited to the case where only slate is used, but can be applied to other materials which can be expected to expand by heat treatment. For example, clay, shale or similar expandable material. Of course, it is necessary to form the clay into pellets before processing.

(Another embodiment) (1) FIGS. 7 to 9 show a modified example of the discharge zone. In the discharge zone DZ, a rake bar 100 having a hollow cross-sectional shape and air-cooled over the hearth 12. Extending in the radial direction, the rake bar 100 is rotatable about its longitudinal central axis. The rake bar 100 is penetrated by a large number of hollow tins 102 extending obliquely downward,
The tin 102 is supported slidably up and down with respect to the bar 100, and the lower end of the tin 102 is in contact with the upper surface of the hearth 12 by gravity. A tension spring 104 is connected to an arm 106 projecting from the bar 100 in the radial direction of the bar 100 in FIG. 8 so as to hold the tin 102 so as to move along the unevenness of the surface of the hearth 12. Further, by pulling the radial arm 106 toward the stopper 107 side and engaging with the stopper 107 side, the tin 102 is maintained at a predetermined angle.

Each hollow tin 102 is connected to a flexible tube 103, which in turn is connected to an air source.
The hollow tin 102 has two roles, one role on the hearth 12 before the slate chips are blown off by a number of consecutive nozzles, not shown, such as the nozzle 78 described above. Air is blown out to cool the expanded slate particles, and the second role is to separate the particles from the hearth 12 so that the particles do not remain on the hearth 12 like rake tin.

Tin 10 between the hearth 12 and the slate particles as described above
When the air from 2 enters, the expanded slate, especially the expanded hearth 1,
There is the benefit that it is easier to leave the 2 and the hearth 12 is cleaned. The air ejected from the tin 102 comes into contact with the hearth 12 so that the tin 102 floats above the surface of the hearth 12, but nevertheless the tin 102
It is kept in contact with the cab formed on 02. As a concrete structure example, Tin 102 is a rake bar 1
The lengthwise movement of 00 causes the hearth 12 to reciprocate in the hearth radial direction. The rake bar 100 is linked to the motor 108 via a crank 110 and a connecting rod 112, and is thereby reciprocally driven.

(2) FIGS. 10 and 11 show still another embodiment of the discharge zone DZ, which is similar to the structure and operation of the apparatus shown in FIGS. 7 to 9 in the following points. . That is, the large number of hollow tins 102 supported by the rake bar 100 are cooled by jet air before blowing the expanded slate chips out of the hearth 12 and the tin 102 causes the expanded slate chips to move to a seventh position.
The expanded particles are prevented from remaining on the hearth 12 in the same manner as described with reference to FIGS. However, in this embodiment the hollow tin 102 is positioned perpendicular to the hearth 12. Due to such a structure, although not shown, the aforementioned nozzle 78
As described above, it is extremely effective in ejecting chips in the ejection zone by blowing air from the nozzle. Particularly, the advantage of such a structure is that it is only necessary to cut the lower end portion of the tin 102 straight, and it is not necessary to install the tin 102 at an inclined angle as described above, so that the processing becomes easy.

(3) As another specific example, the following hearth having an endless structure may be provided. For example, a hearth formed by connecting a large number of tiles is configured to extend forward in a straight line, and any preheating zone, supply zone, processing zone, and discharge zone are sequentially linearly configured as described above. Then, the hearth passes through each zone and then returns to the preheating zone through the return stroke.

(4) In a disc-shaped hearth, a large number of concentric ring-shaped tiles may be arranged adjacent to each other on the surface of the hearth. In such a case, it is desirable that at least tin 81 or 102 be supported by a spring-loaded flat device. The effect of this structure is to prevent the tin from damaging the hearth or the tin itself at the joint between the tiles.

(5) Furthermore, the present invention is not limited to the above-described apparatus and method, and the operating temperature in the processing zone and the preheating zone may be changed, for example, within a temperature range of up to about 200 degrees on both sides. Good.

(6) The material to be treated may be fed onto the hearth by any other suitable means.

(7) As a heating means, the treatment zone and the preheating zone may be heated by means other than the heat storage burner (which is the most economical).

(8) Moving the expanded particles away from the hearth may have different effects. That is, in the illustrated apparatus, a scraper may be provided in the receiving box for charging the expanded material from the hearth. The scrapper may or may not be equipped with nozzles or such air ejection members which eject cooling air towards the surface of the hearth to separate the expanded particles from the hearth.

(9) As a means for cleaning the hearth, for example, an air-cooled rotary brush may be provided in parallel with the manifold 76 and thereafter.

(10) Also provided with reciprocating brushes or such reciprocating movements in place of or in addition to the rakes 80, 82 to ensure the discharge of expanded particles from the hearth 12. You can also

(11) A suitable cooling fluid such as steam may be supplied to the injection nozzle and / or tin instead of air.

(Effects of the Invention) According to the present invention as described above: (1) Distribute the particulate material on the moving hearth 12 and heat-treat the hearth 12 by passing it through the treatment zone in the above-mentioned distribution state. Therefore, as compared with the conventional method and apparatus in which the particles are passed through the converter while being heat-treated while rolling, there is no need to worry about the particles adhering to each other or the particles and the hearth, and the heat-treatment efficiency of the material is improved. The quality of the product is also improved.

(2) Since the heat treatment is performed at a high temperature at which the particles are at least partially melted in the heat treatment zone, the particles can be expanded to the maximum expansion degree while preventing the particle adhesion phenomenon as described above, and have a small specific gravity and light weight. Can produce the following products.

Therefore, when using it for concrete aggregate, etc.,
It is possible to provide a concrete block or the like that is lightweight and has excellent heat resistance.

(3) As a front stroke of the supply zone CZ, empty hearth 12
Through the preheating zone PHZ, since the heating is performed to the same high temperature as the heat treatment zone TZ, in the supply zone CZ, at the same time as the supply, the heat-expandable particles are rapidly heated by the high-temperature hearth 12, Moreover, it is rapidly heated to a temperature at which it can be almost melted and sent to the heat treatment zone TZ together with the hearth 12.

By rapidly heating the particles after feeding them in this way,
Effectively prevent the gas inside the particles from escaping from the particle surface,
Since it can be contained, the particles can be sufficiently expanded.

(4) Preheating zone PHZ for the hearth itself on which particles are placed
And then in the feed zone CZ, the hearth 12
Since the particles on it are heated by the above, not only can the heating be performed in the same manner as, for example, heat dissipation by the furnace wall or combustion gas, but also the particles can be directly and effectively heated from the lower side, and the rapid sealing and Sufficient expansion can be ensured.

Moreover, in the supply zone CZ, since the particle material is distributed on the hearth 12 in a uniform layer that does not exceed the thickness of three particles, there is less variation in the heating effect, and a higher quality lightweight aggregate is obtained. Produced.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of a heat treatment apparatus to which the present invention is applied, FIG. 2 is a horizontal sectional view taken along the line II-II in FIG. 1, and FIG. 3 is a sectional view taken along the line III-II in FIG. III cross section enlarged partial view,
4 is an enlarged detailed plan view showing the discharge zone, FIG. 5 is a sectional view taken along line VV of FIG. 4, FIG. 6 is a sectional view taken along line VI-VI of FIG. 4,
FIG. 7 shows a modified example of the discharge zone, which is a plan view of the same portion as FIG. 4, FIG. 8 is a sectional view taken along line VIII-VIII of FIG. 7, and FIG. 9 is IX-IX of FIG. Sectional view, FIG. 10 is a plan view similar to FIG. 7 showing another modification of the discharge zone, FIG.
The drawing is a cross-sectional view taken along the line XI-XI of FIG.

Front Page Continuation (72) Inventor Aaron Charles Day England, Yorkshire, New York, Lower Worth, Meadow Croft (no house number)

Claims (13)

[Claims] 1. A moving hearth 12 is sequentially passed through a feed zone CZ, a treatment zone TZ and an exhaust zone DZ, and in the feed zone CZ, expandable particulate material 48 such as slate and viscosity is fed onto the hearth 12. In the processing zone TZ, the particulate materials on the hearth 12 can be at least partially melted so that they expand 1000
Heat treatment at high temperature in the range of ℃ to 1300 ℃, discharge zone DZ
In the heat treatment method of the expandable material for forming the lightweight aggregate, which releases the expanded product from the hearth 12,
12, through the preheating zone PHZ between the discharge zone DZ and the supply zone CZ, in the preheating zone PHZ, the empty hearth 12 is at a high temperature similar to the heat treatment temperature of the treatment zone TZ. In the feeding zone CZ, the lightweight aggregate is formed by feeding the particulate material 48 to the hearth 12 immediately after the preheating in a uniform layer that does not exceed the thickness of three particles of the particulate material 48 in the feeding zone CZ. Of heat treatment of intumescent material for heat treatment. 2. The method for heat treating an expandable material according to claim 1, wherein the expanded material is cooled in the discharge zone DZ by spraying a cooling fluid on the expanded material. 3. A method of heat treating an expandable material for forming a lightweight aggregate according to claim 2, wherein expanded particles are discharged from the hearth 12 by a cooling fluid. 4. A rake 80, 82 that reciprocates in the discharge zone DZ.
A method for heat treatment of an expandable material for forming a lightweight aggregate according to any one of claims 1 to 3, wherein the expanded particles are mechanically separated by / 100, 102. 5. Rake 100, 1 for cooling expanded particles
The method for heat treating an expansive material for forming a lightweight aggregate according to claim 4, wherein a cooling fluid is supplied from a plurality of hollow tins 102 of 02. 6. A heat treatment apparatus for expanding an expandable particulate material such as slate or viscosity to produce a lightweight aggregate product, wherein each part is provided in a supply zone CZ, a processing zone TZ and an exhaust zone DZ. Having a moving hearth 12 that circulates through each of the above-mentioned zones in that order, and a hearth 12 in the supply zone CZ.
Material supply means 50, 60, 58 for supplying the pre-processed material to distribute the material over and processed to a high temperature of 1000 ° C-1300 ° C which causes at least partial melting of the material so as to expand the material. Heating means 64, 66, 68, 70 for heating the zone TZ
In the heat treatment apparatus of the expandable material for forming the lightweight aggregate with the discharge means 76, 78 for discharging the expanded product from the hearth 12 in the discharge zone DZ, the discharge zone DZ and the supply zone CZ A preheating zone PHZ is arranged between the preheating zones PHZ, and the preheating zone PHZ is provided with heating means for heating the empty hearth 12, and heat treatment of the expansive material for forming a lightweight aggregate. apparatus. 7. A method for forming a lightweight aggregate according to claim 6, wherein the hearth 12 is formed by connecting a large number of tiles 14 having excellent heat resistance and chemically inertness. Inflatable material heat treatment equipment. 8. The hearth 12 is formed in a circular flat plate shape or an annular flat plate shape, and a solid horizontal surface is configured to rotate around a solid vertical axis. Expansion for forming a lightweight aggregate according to claim 6 or 7, covering most of the said housing, comprising a feed zone CZ, a treatment zone TZ, a discharge zone DZ and a preheat zone PHZ. Heat treatment equipment for conductive materials. 9. To form the lightweight aggregate according to any one of claims 6 to 8, wherein the treatment zone TZ is provided with regenerative burners 64, 66; 68, 70 as heating means. Inflatable material heat treatment equipment. 10. A heat storage type burner 72, 74 is provided as a heating means for the preheating zone PHZ.
Item 10. An apparatus for heat treatment of an expandable material for forming the lightweight aggregate according to any one of items 9. 11. Regarding the circumferential angle and area ratio of each zone, the preheating zone PHZ has a circumferential angle of 90 ° to 144 ° and an area ratio of 25% to 40%, and the supply zone CZ has a circumferential angle. The area ratio is 3 %% to 8% at 10.8 degrees to 28.8 degrees, and the area ratio is 62% at the circumferential angle of 232.8 degrees to 133.2 degrees in the processing zone TZ.
Claim 37, in which the discharge zone DZ has a circumferential angle of 36 to 54 degrees and an area ratio of 10 to 57%.
An apparatus for heat treatment of an expansive material for forming the lightweight aggregate according to any one of items 9 and 10. 12. The lightweight aggregate according to claim 6, further comprising a fluid ejection nozzle 78 for blowing off the expanded particles from the hearth 12 as a discharging means. For heat treatment of expansive material. 13. Lightweight aggregate according to any of claims 6 to 12, comprising reciprocating rakes 80, 82/100, 102 for separating expanded particles in the discharge zone DZ. For heat treatment of intumescent material for forming a.